MODEL 2100-STDX, 2100-LX / WAND OPERATION / PAGE
OF 4
CARE OF THE SENSING WAND AND THE PHOTO-FIBER-OPTIC SENSOR
1. After each day's use extend the wand sections completely and wipe all surfaces dry. This
will reduce corrosion and prevent future difficulty in lengthening the sections. If possible
allow the sections to completely air dry before collapsing and storing the wand. A light film
of oil or silicone grease will help the sections slide and helps to prevent the normal corrosion
which occurs.
2. Treat the sensor boom gently. When swiveling into and out of position grasp only the BOOM,
not the SENSOR BODY or PROPELLER ASSEMBLY. The sensor swivel can be tightened by
adjusting the through-bolt and nut (see back page diagrams).
3. Take care that the electrical cable loop which passes through the sensor swivel does not
protrude from the groove provided for the cable. Carefully take up the slack in the cable
when the loop extends beyond the back side of the swivel bar.
4. The electrical connector is water resistant at the mating faces only and then only when the
two halves are mated. Keep both ends as dry as possible when not in use.
CARE OF THE MODEL 2100 SENSOR
The Sensor of the Model 2100 Current Meter is the single most important part of the instrument and great care
must be observed for its continued accurate output.
Keep the Sensor/Propeller assembly above the stream bed when taking readings and avoid rocks and other
hazards when moving from one measuring site to another. This will prevent damage to the Rotor, Rotor Shaft,
Propeller and the Sensor Body.
Never transport or store the sensor wand with the propeller rotor installed.Use the 1/16" hex screwdriver to
loosen the setscrew and remove the entire rotor assembly when not using the Model 2100. Do not tighten the
set screw any tighter than necessary to keep the rotor in place on the sensor. If too tight, the set screw can
damage the surface of the rotor shaft causing it in turn to damage the inside of the fiberoptic rotor when it is
removed for normal maintenance and cleaning.
Always replace the battery in the Model 2100 Indicator with a fresh one.
1. During rough use check the propeller frequently for frayed leading edges and for cracks. Chipped or
cracked props should be replaced. Frayed leading edges can be brought back to acceptable levels of
operation by reshaping them with 150 grit (or finer) sandpaper. Propellers which show signs of being
bent or misshapen should be discarded.
2. Rotational friction is by far the biggest cause of erroneous data especially at velocities below 2 feet per
second. Check the freedom of rotation frequently especially in turbid water or after rough handling. In
some measuring situations it may be necessary to completely disassemble the rotor and clean the parts
with clear water after each immersion. Use spare rotor assemblies and interchange them often. Never
leave the rotor assembly attached to the sensor after taking readings.
3. Water is the lubricant for the Model 2100 rotor. "Canned air" and spray type degreasers should be
used to regularly clean the "bore" of the Rotor (2100-A27) and the polished surface of the Rotor Shaft
(2100-A26). Avoid oil & grease if possible.
4. The Rotor Assembly (2100-A21) should spin very freely when held in the vertical position (propeller
pointing up) and simply blow lightly on the propeller. If it does not, clean the bore of the Rotor and the
surface of the Rotor Shaft thoroughly.
One method to determine an acceptable level of low-velocity performance by a particular Rotor
Assembly is to perform a "Spin Test" :
Install the Rotor on the sensor, connect the sensor to the Indicator, and place the Indicator in the
COUNT mode. With the propeller pointing up blow very hard straight down on the propeller. At the
